Field of the Invention
The present invention relates generally to a gas turbine engine, and more specifically to a turbine stator vane with an insert and a flexible or compliant seal.
Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
In a gas turbine engine, such as a large frame heavy-duty industrial gas turbine (IGT) engine, a hot gas stream generated in a combustor is passed through a turbine to produce mechanical work. The turbine includes one or more rows or stages of stator vanes and rotor blades that react with the hot gas stream in a progressively decreasing temperature. The efficiency of the turbine—and therefore the engine—can be increased by passing a higher temperature gas stream into the turbine. However, the turbine inlet temperature is limited to the material properties of the turbine, especially the first stage vanes and blades, and an amount of cooling capability for these first stage airfoils.
Turbine stator vanes are often cooled using impingement cooling inserts because the stator vanes do not rotate and thus an insert can be used. High thermal stress occurs in first and even second stage stator vanes, and thus an insert would undergo relatively high movement within the cavity of the airfoil. A flexible seal can be used to maintain a seal even under these relatively large displacements between the insert and the airfoil. However, too much relative movement between the insert and the airfoil cavity would affect the seal performance.